Stop motion



Jul 17', 1923;" I 1.4616876 C. H. T. HAGELSTEIN STOP MOTION V Filed March 14. 1922 2 Skis-Sheet 1 Fig. 1.

T lnanfb1|t Ch. isiun c1 esTein c. H. 'r. HAG EL'STEiN' STOP MOTION Filed Marh 14, 1922 astute-s eet '2 \nvenfor. Chrisfiun HIHugelsTein bymdwkm Patented July 17, 1923.

star

hehht'lt PATENT @WF'HQE...

CHRISTIAN H. T. HAGELSTEIN, 0F BOSTON, TEASSAGHUESETTS, ASSIG-NOR TO THE BEECE BUTTON HOLE MACHINE COMPANY, OF BOSTON, MASSACHUSETTS, A COR PORATION' OF MAINE.

s'ror ivrorron.

Applicationfiled March 14, 1922. Serial No. 543,577.

To' all whom it may concern:

Be it known that I, CHRISTIAN H. T. HAG- ELSTEIN, a citizen of the United States, and resident of Boston, county of Suffolk, State of Massachusetts, have invented an improvement in Stop Motions, of which the following description, in connection with vide an improved stop motion which is.

capable of use withmachincs operating at high speed and which will function to bring,

the machine to rest at the end of the cycle of operations with a cushioned movement, thus eliminating any jar or shock which is detrimental to the machine. v

In order to give an understanding of the invention I have illustrated in the drawings a selected embodiment thereof which will now be described after which the novel features will be pointed out in the-appended claims. i

Fig. 1 shows in elevation a portion of a machine having one form of my improved stop motion applied thereto.

Fig. 2 is a top plan view of Fig. 1.

Fig. '3 is a side elevation. 1

Fig. 1 is a bottom plan view of a portion of the machine to which the stop motion is applied and showing the under side view of the stop motion. I Y 1 Fig. 5 is a detail of the cam for releasing the locking member. i W a i igs. 6 and 7 are end views showing the stop cam and a portion of the stop dog, in different positions.

Fig. 8 is a view of the housing enclosing the spring which controls the recoil preventing latch. i

Fig. 9 is a section on the line 9--9, Fig. 6.

My improved stop motion is adapted to be used in connection with a. great variety of machines that are constructed to perform a pre-determined cycle of operations and-then to come to rest, and merelyas illustrating a machine of this type I would refer to sewing machines that are adapted to sew a short seam and then come to rest. I wish to have it clearly understood, how

ever, that my invention is applicable to a variety of machines and is not confined in its use to any particular machine.

The invention herein shown is in-some respects similar to the device shown in United tates Patent No. 1,173,162, Feb. 29, 1916. i

In the drawings I have illustrated at 1 a portion of the frame of a machine with which the stop motion is associated, said machine being of the type which is provided with a drive shaft 2 by which it is operated. This drive shaft is shown as having a fast and loose pulley thereon, 3. indicating the loose pulley which is loosely mounted on the shaft, and 1- indicating the fast pulley which is rigid with the shaft.

(lo-operating with the pulleys is a driv ing belt 5 which isoadapted tobe shifted from the loose pulley to the fast pulley and vice versa by means of a belt shipper 6. This belt shipper is carried by an arm 7 7 which is fast on a rock shaft 8 journalled in'suitable bearings 9 carried by the frame 1. The turning of the rock shaft operates through the belt shipper 6 to shift the belt from the loose pulley to thefast pulley to start the machine and from the fastpulley tothe loose pulley to stop the machine.

Means are provided for turning'the rock shaft manually to start the machine, such means comprising a hand lever .49 fast to the shaft and by which the shaft may be turned-by hand, and also comprising an arm 10 fast to and extending laterally from the shaft and to which a foot treadlemay be attached by a connection 11. 1 f

When the shaft has been turned to throw the belt onto the fast pulley, as shown in the drawings the belt shipper is locked in its position by means of a latch 12 pivotally mounted on an arm 13 carried by the frame and acted upon by a spring 14 which tends to hold it in operative position. This latch is released automatically at the end of' the icycle of operations by means of a releasing cam 15 which is secured to and rotates withthe main cam 16 ofthe machine, the latter being connected to and driven by the-driv ing shaft 2. For this purpose thelatch 12 has integral therewith an arm 17 having a cam face 18. engaged by the releasing Loam 15 at aprerdetermined point Lin-the cycle of operations. V 1

When the latch 12 is released the rock shaft 8 is turned to shift the belt into the 29 of the cam during the dotted lineposition therebyfto carry the beltonto the loose pulley by means of one or more springs 19 which are situated be- ;ytween; the-. frame; 1 and a b racket or frame 1 20 iiikhfl is; rigd Wit the pro ck. sha ft 1 8.

The parts thus far described are or may be all as usual in said above-mentioned patent.

For bringing the. shaft-2to rest when, the belt'shipper is thrown onto the loose pulley lgprovi-de a stop cam 21 whichis fast on the shaft 2- and whiclr co-operates with a stopdog 22 slidably mounted in bearings formed on'the -fran1e 20 and acted upon by a spring 2 4tten-ding to move it toward the stop cam. This spring 24: surrounds the 'shank'25'of t he stop dog and-is confined between a collar 26 adjustable on said shank and one of the bearings 23. The collar 26' "co-operates with the otherybearing '23 to limitthe' spfling-impelled movement of the stop dog. i l lthen the parts are in the pos ition shown in Fig, 2 with the belt on the fast pulley the'stop dog 22 issituated out of linewith the stop cam 21. As soon asthe latch 12 is released at'the proper point in the cycle of operations,' the frame' 20 is moved into the dotted line-position Fig. 2' by the springs ltlthe'fiebybfringing the stop dog into'the path O-flille: stop cam 21.

The stop gcam-=2l is shown as having a high point :27 and as having an eccentric curved face 28 on the backside of thehigh' poirit and a straight face 29 on the front side" of the high point.

n1 order tofbring the-shaft-2 to rest with acushioned movementand -without any appreciable shock or jar] have" designed the f partsso thatg after the-latch isreleased and 'jshownin Fig.

The parts timed so that when the latch -is released an'dthe stop dog is moved into the path of the cam the cam will be it ap- V proximately in --a position with the low portibnof the cam-opposite said stop dog.,- As the-cam continues to; rotate due to the -I no-' ment'um of the machinethe face 29 of the cam wilh engage the end of the stop dog 22 f thusforcin g the stop dog' backwar'dly -.againstthe 'action of the spring 24.-

The shape ofthe} cam is} such, with relas tion to the tensionofthe-spring 24:;thatthe momentum ofthera pidly moving partswill carry the" high point of the cam past the end of the stop dog, as shown in Fig 6, thus afully compressing the spring 24. The tenflfi sionlof the spring is such'th'at the resistanceit offers to the-movement ofthe ca'm while thefaee 29 is wiping past theend of the stop dog will very materially reduce the momen tum of the par-ts without, however, bringing the shaft entirely to rest. As soon as the high point of thei'cam passes-the high point of the stop dog then the latter will move :time with the end of the stop dog 22 will bring the machine to rest with an easy movement.

It will thus be seen that with this construction the first rotation of the shaft 2 after the belt has been shifted onto the loos'e pulley will very materially reduce the mo- Inentum of the parts without bringing the shaft to rest, andthat the final stoppageof the machine occurs when the face 29 of the cam a second time engages the end of the stop dog 22.

In order to prevent any rebound-after the machinehascome to rest I provide astop latch 30 which is pivoted in thesidejof a cup-shaped disk 31 that is fast on the shaft and is situated adjacent the stop cam 21. This latch 30 isacted upon by -a'-spring 82 which tends ;to hold it-in its operative position and said latch isformedwith-theffinger or extension 33 I which limits the spring-' impelled movement thereofa The latch is shown as operating in an openin'giA i'nthe disk 31 and as pivoted on the radial "pivot 35.- This can be readily pushed inwardly against the action of the spring in the'direction ofthe arrow. Figflt); and during the rotation of the'shaft 2 after the stop dog has been moved into the path of the cam sai'd' stop dog will Wipe over the latch 30 and the latter will lee-retracted against'the action of the spring 32 as-the stop dog passes it. When the stop doghas passed over the latch 30,-however, it springs outwardly behind the dog, as shown in Fig. 7

andthus prevents any rebound or backward movement of the shaft rest.

The latch-releasing cam 15 is] shown as mounted on a plate 36 which is adjustably after it comes to secured to the cam 16and isheld in posi tion by the clamping screw 37'. With this construction the cam may be' r'eadily adjusted so that the latch will be released at the-proper time. k

Iclaim. i 1

1. In a stop 'motiomth'e' combination with a driving shaft, of adriving belfitherefor and a belt shipper to connect the driving'belt toor disconnect it from the shaft, of a'stop cam fast on the driving sh-a-ft,saidstop earnhaving a continuous peripheral cam face, sald face being formed with a low portlon, one end of which merges into a relativelyshort straight portion of increasing radius' and the other end of which merges into a' convexly-curved portion which is considerably longer than the straight portion and which also has a progressively-increasing radius, said straight portion and convexlycurved portion meeting and forming a high point at the cam, a stop dog, a spring acting on the stop dog and adjustable as to its tension, said stop dog being connected to the belt shipper so that when the belt is connected to the driving shaft the stop dog is out of the path of movement of the stop cam but when the belt is disconnected from the driving shaft the stop dog is carried into the path of movement of the stop cam and engages the continuous cam face thereof, the shape of the cam face and the tension of the spring having such relation to the momentum and speed of the shaft that when the stop dog is brought into engagement with the cam the high point thereof will be carried past the stop dog once thereby largely reducing the speed of the shaft and said shaft will be brought to rest when the straight portion of the cam face comes a W second time into engagement with the stop dog.

2. In a stop motion, the combination with a driving shaft, a driving belt therefor and means to connect the driving belt to or disconnect it from the shaft, of a stop cam fast on the driving shaft, said stop cam having a high point, a face of progressively diminishing radius on the front or forward side of the high point and a curved eccentric face also of progressively diminishing radius on the back side of the high point, a springpressed stop dog, and means to cause the stop dog to engage the stop cam by the act of disconnecting the driving belt froin the driving shaft, the shape of the stop cam and the spring pressure on the stop dog having such relation to the momentum and speed of the shaft that when the stopdog is brought in to engagement with the cam the high point of the cam will be carried past the stop dog once thereby largely reducing the speed of the a shaft and said shaft will be brought to rest when the first-named face of the stop cam comes a second time into engagement with the stop dog, and a spring-pressed latch rotatable with the stop cam and adapted to engage the stop dog when the shaft comes to rest thereby to prevent rebound.

In testimony whereof, I have signed my name to this specification.

CHRISTIAN H. 'r. HAGELSTEIN. 

